#pragma once

#include<iostream>
#include<string>
#include<vector>
#include<unordered_map>
#include<fstream>
#include<cassert>
#include<cstdlib>


#include"../comm/log.hpp"
#include"../comm/util.hpp"
#include"mysql/mysql.h"

namespace ns_model
{
    using namespace std;
    using namespace ns_log;
    using namespace ns_util;

    struct Question
    {
        std::string number;//题目编号
        std::string title; //题目标题
        std::string star;  //题目难度
        std::string desc;  //题目的描述
        std::string header;//题目预设给用户在线编辑器的代码
        std::string tail;  //题目的测试用例，需要和header拼接，形成完整代码
        int cpu_limit;     //题目的时间要求(s)
        int mem_limit;     //题目的空间要求(KB)
    };

    const std::string oj_questions = "oj_questions";

    const std::string host = "127.0.0.1";
    const std::string user = "oj_client";
    const std::string passwd = "123456";
    const std::string db = "oj";
    const int port = 3306;

    class Model
    {
    public:
        Model()
        {
        }
        ~Model()
        {}

        bool QueryMysql(std::string sql, vector<Question> *out)
        {
            //连接数据库
            //创建mysql句柄
            MYSQL* my = mysql_init(nullptr);

            //连接数据库
            if(nullptr == mysql_real_connect(my, host.c_str(), user.c_str(), passwd.c_str(), db.c_str(), port, nullptr, 0))
            {
                LOG(FATAL) << "连接数据库失败" << "\n";
                return false;
            }

            //需要设置该连接的编码格式，因为默认是latin的，而mysql是utf8的，会出现乱码
            mysql_set_character_set(my, "utf8");

            LOG(INFO) << "连接数据库成功" << "\n";

            //执行mysql语句
            if(0 != mysql_query(my, sql.c_str()))
            {
                LOG(WARNING) << sql << "execute error!" << "\n";
                return false;
            }   

            //提取结果，是malloc出来的需要释放
            MYSQL_RES* res = mysql_store_result(my);

            //结果分析
            int rows = mysql_num_rows(res);//获取行数
            int cols = mysql_num_fields(res);//获取列数

            struct Question q;
            for(int i = 0; i < rows; i++)
            {
                MYSQL_ROW row = mysql_fetch_row(res);
                q.number = row[0];
                q.title = row[1];
                q.star = row[2];
                q.desc = row[3];
                q.header = row[4];
                q.tail = row[5];
                q.cpu_limit = atoi(row[6]);
                q.mem_limit = atoi(row[7]);

                out->push_back(q);
            }

            //释放res
            mysql_free_result(res);
            //关闭mysql连接
            mysql_close(my);

            return true;
        }

        bool GetAllQuestions(vector<Question> *out)
        {
            std::string sql = "select * from ";
            sql += oj_questions;
            return QueryMysql(sql,out);
        }

        bool GetOneQuestion(const std::string& number, Question* q)
        {
            bool res = false;
            std::string sql = "select * from ";
            sql += oj_questions;
            sql += " where number=";
            sql += number;
            vector<Question> result;
            
            if(QueryMysql(sql, &result))
            {
                if(result.size() == 1)
                {
                    *q = result[0];
                    res = true;
                }
            }

            return res;
        }

    };

}